[bdwjn]

Oh there's more:

9 - 3 ^ 2 = 0

9 -3 ^ 2 = 18 ???

pi = 3.1415926536

2 pi = 5.1415926536 ???

sin(3.1415926536 radians) = -0

sin(pi radians) = Incompatible units ???

[wizofaus]

Seems to assume + if an arithmetic operator is missing?

[tonyonodi]

This is correct, the idea is that you can type things like "6 foot 3 inches" and have it evaluate as an addition. But the example shown above is definitely a problem, I'll try to think of a work around.

[wizofaus]

I'd think that rule only makes sense after a symbol representing a unit (including potentially 6'3"). Certainly <number> <named constant> should logically assume multiplication.